What
is asbestos?
Asbestos is the name for a group of naturally occurring
silicate minerals that can be separated into fibers.
The fibers are strong, durable, and resistant to heat
and fire. Asbestos materials are also long, thin and
flexible, so that they can even be woven into cloth.
Because of these qualities, asbestos has been used in
thousands of consumer, industrial, maritime, automotive,
scientific and building products. During the twentieth
century, some 30 million tons of asbestos were used
in industrial sites, homes, schools, shipyards and commercial
buildings in the United States.
There are several types of asbestos fibers, of which
three have been used for commercial applications: (1)
Chrysotile, or white asbestos, comes mainly from Canada,
and has been very widely used in the US. It is white-gray
in color and found in serpentine rock. (2) Amosite,
or brown asbestos, comes from southern Africa. (3) Crocidolite,
or blue asbestos, comes from southern Africa and Australia.
Amosite asbestos and crocidolite asbestos materials
are called amphiboles. This term refers to the nature
of their geologic formation.
Other asbestos fibers that have not been used commercially
are tremolite asbestos, actinolite asbestos and anthophyllite
asbestos, although these materials are sometimes contaminants
in asbestos-containing products. It should be noted
that there are non-fibrous, or non-asbestiform, variants
of tremolite, anthophylite and actinolite, which do
not have the adverse health consequences that result
from exposure to commercial forms of asbestos.
What
are asbestos-containing products?
What is common to many asbestos-containing products
is that they were (are) used to contain heat (i.e. thermal
insulation.) It is impossible to list all of the products
that have, at one time or another, contained asbestos.
Some of the more common asbestos-containing products
are pipe-covering, insulating cement, insulating block,
asbestos cloth, gaskets, packing materials, thermal
seals, refractory and boiler insulation materials, transite
board, asbestos cement pipe, fireproofing spray, joint
compound, vinyl floor tile, ceiling tile, mastics, adhesives,
coatings, acoustical textures, duct insulation for heating,
ventilation and air conditioning (HVAC) systems, roofing
products, insulated electrical wire and panels, and
brake and clutch assemblies.
Some of these products contained a very high proportion
of asbestos, while others contained small amounts.
Since
asbestos causes many diseases like malignant mesothelioma,
pleural mesothelioma, peritonial mesothelioma. People
are suggested to be aware of this asbestos and its usage.
Of these mesothelioma asbestos diseases is effecting
when a person is highly exposed to asbestos.
# # #
Sources of National Cancer Institute Information
Mesothilioma, Mesotheliema,Mesothiliema,Mesotheleoma
Mesosthelioma, Masesthilioma information: |
|